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 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.annotation.processing;

import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import java.util.Set;
import java.lang.annotation.Annotation;

/**
 * An annotation processing tool framework will {@linkplain
 * Processor#process provide an annotation processor with an object
 * implementing this interface} so that the processor can query for
 * information about a round of annotation processing.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @since 1.6
 */
public interface RoundEnvironment {

  /**
   * Returns {@code true} if types generated by this round will not
   * be subject to a subsequent round of annotation processing;
   * returns {@code false} otherwise.
   *
   * @return {@code true} if types generated by this round will not be subject to a subsequent round
   * of annotation processing; returns {@code false} otherwise
   */
  boolean processingOver();

  /**
   * Returns {@code true} if an error was raised in the prior round
   * of processing; returns {@code false} otherwise.
   *
   * @return {@code true} if an error was raised in the prior round of processing; returns {@code
   * false} otherwise
   */
  boolean errorRaised();

  /**
   * Returns the root elements for annotation processing generated
   * by the prior round.
   *
   * @return the root elements for annotation processing generated by the prior round, or an empty
   * set if there were none
   */
  Set<? extends Element> getRootElements();

  /**
   * Returns the elements annotated with the given annotation type.
   * The annotation may appear directly or be inherited.  Only
   * package elements and type elements <i>included</i> in this
   * round of annotation processing, or declarations of members,
   * constructors, parameters, or type parameters declared within
   * those, are returned.  Included type elements are {@linkplain
   * #getRootElements root types} and any member types nested within
   * them.  Elements in a package are not considered included simply
   * because a {@code package-info} file for that package was
   * created.
   *
   * @param a annotation type being requested
   * @return the elements annotated with the given annotation type, or an empty set if there are
   * none
   * @throws IllegalArgumentException if the argument does not represent an annotation type
   */
  Set<? extends Element> getElementsAnnotatedWith(TypeElement a);

  /**
   * Returns the elements annotated with the given annotation type.
   * The annotation may appear directly or be inherited.  Only
   * package elements and type elements <i>included</i> in this
   * round of annotation processing, or declarations of members,
   * constructors, parameters, or type parameters declared within
   * those, are returned.  Included type elements are {@linkplain
   * #getRootElements root types} and any member types nested within
   * them.  Elements in a package are not considered included simply
   * because a {@code package-info} file for that package was
   * created.
   *
   * @param a annotation type being requested
   * @return the elements annotated with the given annotation type, or an empty set if there are
   * none
   * @throws IllegalArgumentException if the argument does not represent an annotation type
   */
  Set<? extends Element> getElementsAnnotatedWith(Class<? extends Annotation> a);
}
